Hmmm, I pass cyclists most training rides - cycling is very popular for sport and fitness here, less so commuting though although ebikes among tourists is very common. I usually say "Bom dia" (Good morning) as I go past and get the same greeting in return. Heck, here in Southern Portugal, most pedestrians or anyone out and about greet everyone regardless and if we are in a Group, we'll get some banter going with locals wherever we are. Had some elderly folks making me feel I was in the Tour de France yesterday on a hill, such was their support as they sat by the roadside! It's a friendly place. Waving and greeting is the norm, riding or no.
Sometimes I do fail to say hello though, like today, went past a few individuals but I was in time trial mode and doing between 25-30mph, concentrating - knackered towards the end so unlikely to say anything! I always pass wide so no probs.
It isn't the same as cycling in a dense suburb, let alone a city, here. In Amsterdam, Copenhagen, Ghent, it is all bells and warning etc...here, very tranquil, lots of personal space, mostly empty roads, low population density. Lovely.